INFO: task syz.3.7564:26415 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.7564 state:D stack:26056 pid:26415 ppid:22899 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6a9/0xcc0 kernel/locking/mutex.c:747 sync_bdevs+0x1af/0x330 block/bdev.c:1076 ksys_sync+0xc6/0x170 fs/sync.c:105 __ia32_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f568bd9c799 RSP: 002b:00007f568cc1c028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f568c015fa0 RCX: 00007f568bd9c799 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f568c015fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f568c016038 R14: 00007f568c015fa0 R15: 00007ffc53bde198 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d132060 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d132060 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d132060 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 3 locks held by kworker/u4:2/42: 2 locks held by getty/5531: #0: ffff8880318ba0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217 1 lock held by udevd/19443: #0: ffff888021f4f4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805 1 lock held by syz.3.7564/26415: #0: ffff888021f4f4c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1af/0x330 block/bdev.c:1076 4 locks held by syz.8.8198/28544: 1 lock held by syz.1.8204/28558: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf3d/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 22132 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:80 [inline] RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline] RIP: 0010:unwind_next_frame+0x4a3/0x2970 arch/x86/kernel/unwind_orc.c:494 Code: 74 24 48 48 89 d8 4c 29 e0 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 4d 8d 3c 44 4c 89 f8 48 c1 e8 03 0f b6 04 10 <84> c0 75 3e 4d 63 2f 4d 01 fd 4c 89 ef 4c 89 f6 e8 98 e3 4b 00 49 RSP: 0018:ffffc90000007378 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffffffff8ed369c8 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 00000000000f0132 RDI: 00000000000f0133 RBP: ffffffff8ed369c8 R08: ffffc90000007510 R09: 0000000000000006 R10: 0000000000000004 R11: 0000000000000100 R12: ffffffff8ed369c8 R13: 00000000000f0132 R14: ffffffff86374f88 R15: ffffffff8ed369c8 FS: 000055557a1e0500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe41a5e7158 CR3: 000000008d5c8000 CR4: 00000000003506f0 Call Trace: arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] kmem_cache_alloc_node+0x14c/0x320 mm/slub.c:3540 __alloc_skb+0x103/0x2c0 net/core/skbuff.c:643 skb_copy+0x13d/0x7a0 net/core/skbuff.c:1987 mac80211_hwsim_tx_frame_no_nl+0xca9/0x11a0 drivers/net/wireless/virtual/mac80211_hwsim.c:1840 mac80211_hwsim_tx_frame+0x1b5/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2176 mac80211_hwsim_beacon_tx+0x3e9/0x780 drivers/net/wireless/virtual/mac80211_hwsim.c:2269 __iterate_interfaces+0x243/0x500 net/mac80211/util.c:766 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:802 mac80211_hwsim_beacon+0xbb/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2295 __run_hrtimer kernel/time/hrtimer.c:1750 [inline] __hrtimer_run_queues+0x520/0xc40 kernel/time/hrtimer.c:1814 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1831 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] RIP: 0010:deref_stack_reg+0x5b/0x240 arch/x86/kernel/unwind_orc.c:403 Code: c1 e8 03 48 89 44 24 10 80 3c 28 00 74 08 48 89 df e8 b9 e8 a3 00 48 89 5c 24 18 4d 8b 77 08 49 8d 5f 10 49 89 dd 49 c1 ed 03 <41> 80 7c 2d 00 00 74 08 48 89 df e8 95 e8 a3 00 48 89 5c 24 08 4d RSP: 0018:ffffc900131d79d8 EFLAGS: 00000a06 RAX: 1ffff9200263af62 RBX: ffffc900131d7b18 RCX: ffff8880784a1e00 RDX: 0000000000000000 RSI: ffffc900131d7f48 RDI: ffffc900131d7b08 RBP: dffffc0000000000 R08: ffff8880784a1e00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000000 R12: ffffc900131d7b08 R13: 1ffff9200263af63 R14: ffffc900131d0000 R15: ffffc900131d7b08 unwind_next_frame+0x1789/0x2970 arch/x86/kernel/unwind_orc.c:648 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 ref_tracker_alloc+0x1b7/0x4c0 lib/ref_tracker.c:209 __netns_tracker_alloc include/net/net_namespace.h:350 [inline] netns_tracker_alloc include/net/net_namespace.h:359 [inline] get_net_track include/net/net_namespace.h:376 [inline] sk_alloc+0x1b1/0x360 net/core/sock.c:2164 inet_create+0x7a0/0xfe0 net/ipv4/af_inet.c:325 __sock_create+0x4a6/0x940 net/socket.c:1570 sock_create net/socket.c:1626 [inline] __sys_socket_create net/socket.c:1663 [inline] __sys_socket+0xd7/0x1a0 net/socket.c:1714 __do_sys_socket net/socket.c:1728 [inline] __se_sys_socket net/socket.c:1726 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1726 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe41a39e007 Code: f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 b8 29 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff17c0e458 EFLAGS: 00000206 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fe41a39e007 RDX: 0000000000000006 RSI: 0000000000000001 RDI: 0000000000000002 RBP: 00007fff17c0eb5c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 00000000000001f8 R13: 00000000000927c0 R14: 000000000013b7da R15: 00007fff17c0ebb0